That's a little less range than stated for the refreshed FCV-R concept revealed by Toyota early last month, and it's unclear whether the production vehicle will use the same drivetrain layout.

Toyota has concentrated on increasing the energy density of its fuel cells, allowing it to do more with less hydrogen.

That also frees up space for batteries as part of a fuel cell-based hybrid system. A 21-kilowatt-hour battery pack--marginally smaller than the battery found in a Nissan Leaf--helps boost the FCV-R Concept's range.

After driving the prototype car, Autoweek estimated 0-to-60-mph performance of around 9 seconds and an output of 150 horsepower from the prototype car, adding that the prototype was "much more fun to drive than...a Prius".

Thanks to electric torque, the prototypes offered enough power to chirp the tires off the line, though the car is more likely to be focused on efficiency more than on outright fun.

A concept version of the eventual production car should appear at the upcoming Tokyo Auto Show--so we'll know more about the car's design in late November.